When the 2013 NFL season gets going in September, the hype spawned by the draft process will fall away and we'll see what this rookie class is really made of. Some first-year players will step into starting roles and produce immediately, while some will take a back seat with their respective teams as they continue to develop their skills. And of course, some will just fade into obscurity.

Harrison: Post-draft Power Rankings

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Last season, we saw players like Seattle Seahawks linebacker Bobby Wagner and Washington Redskins running back Alfred Morris emerge from the shadows and become stars. Neither was being talked about much a year ago, but both went on to play major roles for their respective teams in 2012. This year, I thought I'd try to get ahead of the curve and pick out some rookies who lack buzz but look primed to be immediate difference makers.

Now, when it comes to the list below, you won't see anyone who is widely expected have an impact this season, like Luke Joeckel, Eric Fisher or Tavon Austin. Those guys will all be considered disappointments if they don't make their presence felt. I wanted to focus on players who have, more or less, flown under the radar.

So here are nine rookies (listed in alphabetical order) who seem to be in the right place at the right time to contribute in 2013 -- and all of them were drafted after Round 1.

The Saints have a need at left tackle, with Jermon Bushrod having departed to the Chicago Bears via free agency. Although Armstead needs to work on his technique, he has a chance to start in Week 1. The Arkansas-Pine Bluff product was outstanding at the NFL Scouting Combine (where he clocked a 4.71-second 40-yard dash) and in postseason all-star games. He has the toughness, intelligence and work ethic that usually come from playing at a small school. In that way, he reminds me of someone the Dallas Cowboys plucked from relative obscurity when I worked for the team: Rayfield Wright, the Hall of Fame offensive lineman drafted out of Fort Valley State in 1967. At Senior Bowl practices, Armstead did a great job against Cornelius Washington, the Georgia defender who went to the Chicago Bears in the sixth round.

Broncos quarterback Peyton Manning will love Ball because of his abilities as a runner and as a pass-catcher. He's a tough runner with good hands -- and he does not fumble. Not to mention, he's a good blocking back. Ball is smart, has a good work ethic and is a very good person. Denver is known for using the play-action pass; I don't think Ball will see eight men in the box very often. If Ball had been with the Broncos last season, they might not have lost to the Baltimore Ravens in the playoffs -- they missed out on about seven first downs, and Ball's the kind of guy who will get you a first down when you need one.

This was a very good second-round pick by the Patriots. Dobson is faster than departed veteran Brandon Lloyd; he should be able to step in for Lloyd and make an immediate impact on New England's passing game. The Marshall product was the best receiver at the Senior Bowl and dazzled at his pro day (running the 40-yard dash in 4.42 and 4.44 seconds). He boasts very good hands and big-play ability. One could make a highlight reel out of the catches he made against East Carolina in 2011 and Purdue last season. He should also help out on special teams.

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Logan should start as a rookie for the Eagles. He's a lot like Mike Patterson -- the defensive tackle who just left via free agency -- except Logan is better. He's strong (Logan had 30 reps on the bench press at the combine), has outstanding quickness for the position and is able to get off of blocks. He's also a good pass rusher for a defensive tackle. Logan wore No. 18 at LSU -- which is an honor given to the player who best represents the team, both on and off the field.

Mathieu typifies the "high risk, high reward" prospect. He's a really good player who kind of defies the laws of gravity; he's not that tall and he's not that fast, but he makes plays. The key, of course, is to keep Mathieu out of trouble. (He was kicked off the football team at LSU before last season because of substance-abuse issues.) Fellow LSU product Patrick Peterson should be able to help him stay on the right path. Arizona coach Bruce Arians said shortly after Mathieu was drafted that he'd slot in at safety, but I think they'll end up using him more like a third cornerback. He'll also contribute on special teams.

McDonald is a great steal. He should step right in and contribute from Week 1 as the Niners' second tight end, out-producing the departed Delanie Walker in that capacity. He has the speed and coordination to play the position and possesses very good hands, though he must learn to block better.

The strong and athletic Short is a good penetrator -- he had a knack for blocking kicks at Purdue -- who should boost the Panthers' run defense as a Week 1 starter. When you play on a state championship high school basketball team in Indiana, as Short did, you've got to be a pretty good athlete. Short, who did not run at the combine, completed the 40-yard dash in 5.08 and 5.09 seconds at his pro day. The tougher you coach him, the better he's going to be.

Warford did not run well at the NFL Scouting Combine (notching a 5.58-second 40-yard dash), but Lions coach Jim Schwartz told me he's not worried about that. He just wants someone who can stay in front of pass rushers, and that's something Warford can do. He's strong, moves well for his size and has a good chance to start in Week 1. He does, however, need to control his weight. I know that another team in the NFC was prepared to make Warford a first-round pick if the player they drafted hadn't been available, which should tell you something. Warford is the first offensive lineman out of Kentucky to be drafted in the third round or higher since Dermontti Dawson went 44th overall in 1988.

Williams is a hard-working guy with big-play ability; he had 34 catches of 20 yards or more in 2012, the most in college football. He has very good hands and runs better than his 4.52 40 would indicate. He also possesses the ability to catch the ball over his shoulder -- he's very good at that. Williams is primed to exceed expectations; I think he's got a chance to start over veteran receiver Miles Austin. If that happens, he should see plenty of opportunities as defenses roll their coverage toward No. 1 receiver Dez Bryant.